Median

A measure of the center point of a set of numerical data. It may be used
in situations such as when have scored a number of suppliers on their
capability and want to know which 50% are the best.

The median can be found by sorting the numbers into numeric order and
selecting the middle number. If there are an even number of numbers, then
the average of the middle two numbers is used. Thus the median of 1 2 4 5
6 is 4, and the median of 1 2 4 5 is 3.

The advantage of the median is that it is not affected by outlier
numbers (like 256 in the lists above). However, it is only one number and
does not take the value of the other numbers into account.

Whilst the Median gives a measure of central tendency, the common method
of measuring the spread of a set of numbers is the Standard Deviation.

Other methods of measuring central tendency are Mean (or Average) and
Mode.